1. Field
The technology described herein relates to a brightness adjusting apparatus of a reflective type liquid crystal display device and a program of a game machine. More specifically, the technology described herein relates to a brightness adjusting apparatus of a reflective type liquid crystal display device and a program of a game machine, applicable to a portable terminal such as a portable type liquid crystal game machine, a PDA and etc.
2. Description of related Art
One example of such a kind of conventional reflective type liquid crystal display device is disclosed in a Japanese patent No. 8-241067 [G09G 5/06, G06T 1/00, G06T 11/00] laid-open on Sep. 17, 1996. In a video accelerator board device of this reference, a true color code determined by a vectorial sum of respective elements of R (red), G (green) and B (blue) is converted by using a correction coefficient matrix, and deviance between a color determined by the true color code and a displayed color actually displayed on the display is corrected.
In a case of controlling display of the reflective type liquid crystal display device utilizing the video accelerator board device of this reference, it is possible to adjust a displayed color on a display as described above. In general, the portable game machine and etc. provided with the reflective type liquid crystal display device is utilized indoors and outdoors, illuminated in a light of a fluorescent and a natural light such as sunlight etc. Accordingly, brightness is determined depending on a usage environment. A brightness adjusting function is thus not provided. However, there is a problem that in intensive sunlight the screen of the reflective type liquid crystal device wholly becomes bright while in weak sunlight it wholly becomes dark. The character (object) is therefore hidden under the background and it is difficult for the user to view the screen.
Even if a brightness adjusting function is provided for avoiding this problem, a mere brightness adjustment as in a liquid crystal display of a backlight system makes a whole screen light or dark and therefore, the problem is not yet solved.